1. Is there any useful information that can be obtained from these log
entries, or do we simply need to change to a more verbose log level and
wait for slapd to die again?
2. If we need to change our log level, what is a suggested level? Right
now we're using "loglevel sync stats". Would it be wise to change the
log level to -1 (any)? These are production servers, and I imagine
that'd be a huge performance hit.
3. Also, we're logging asynchronously at the moment. Should we disable
this while debugging?

I would suggest you
(a) Upgrade to 2.4.21
(b) Fix your tcmalloc build
(c) If the problem still occurs, run slapd under gdb so you can get a
backtrace of some kind.
Make sure your OpenLDAP build, etc, has debugging symbols.
--Quanah
--
Quanah Gibson-Mount
Principal Software Engineer
Zimbra, Inc
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